ARM: new SoC support for v5.9

There are three SoC families newly dded to the 32-bit and
64-bit Arm architecture code in the kernel this time:

 - Daniel Palmer adds initial support for two chips made by MStar, a
   taiwanese SoC manufacturer that became part of Mediatek in 2012. For
   now, the added support is fairly minimal, with just two of its
   Cortex-A7 based 32-bit camera chips getting support for a limited
   set of on-chip peripherals.

 - Lars Povlsen from Microchip adds support for their new Sparx5
   family of ethernet switch chips using 64-bit Cortex-A53 cores.
   These are descended from earlier VSC7xxx SparX and Ocelot chips
   using 32-bit MIPS cores.

 - Daniele Alessandrelli from Intel adds support for the new Keem Bay
   SoC for computer vision, built around a Movidius VPU with Linux
   running on Arm Cortex-A53 cores.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>